A desperate grunting sound reaches my ears. It is coming from Chris, my climbing partner, who is los­ing in his struggle with grav­ity. He is the equivalent of five sto­reys above me, and beyond him I can see the top of the wall, still three rope lengths away.

Magazine

Jan - Mar 1997

"Morality is like art: it is the ability to draw a line somewhere." —G. K. Chesterton
Lately I have been thinking about ecorealism, a term used by Gregg Easterbrook in his book A Moment on the Earth to describe an environmental position that avoids the extremes of both the doomsday prophecies of the left and the bulldozer policies of the right. Ecorealists, he says, don't shut their eyes to environmental abuse, but neither do they ignore the progress being made towards sustainable life on planet Earth.
I've been thinking about the term in relation to arguments about what constitutes a valid experience of nature and what oversteps the mark. For example, should people be allowed to swim with dolphins, or only watch them from a boat? Should flights over national parks be banned because they disturb the tranquillity of people on the ground? Should boaties dispose of waste in the sea? Should trampers wash their dishes in a river?
What started this train of thought was a letter taking me to task for lighting a campfire near the headwaters of the Blue River a remote and rarely visited area west of Haast Pass. Along with a writer friend, I had been retracing a journey made by "Mr Explorer" Douglas in the 19th century. It was a cold night, and there was an abundance of fallen branches. Picturing Douglas puffing on a pipe as he prodded the embers, we felt stirred to emulate him, warming ourselves as we pondered his 40 years lived in the wilderness of South Westland.
Evidently, we transgressed. Blotted our conservationist copybooks. Forget the fact that our modest camp was a speck on the edge of a plain several kilometres long and at least a kilometre wide. That the chances of anyone stumbling across a charred log from our fire were about as great as spotting the last moose in Fiordland or finding a kakapo nesting in one's sleeping bag. "The days of pioneering are over," writes my correspondent. Put on another layer of fleece and leave the timber to rot.
Am I alone in thinking that the ordinances of environmental virtue are becoming unbearably stringent? In a recent article in Outside magazine entitled "Is Anything OK Anymore?" writer Jack Hitt finds that a "scolding puritanism" is rampant in the outdoor community. It is no longer enough to treat nature with respect—to "tread lightly" on the land. "Sorry, pack-it-in­pack-it-out is yesterday's beatitude," he writes. "Now the Leave No Trace folks can be found on the Internet, vehemently thinking and rethinking the minutest details of back country etiquette, mulling all the ways in which we grind our heavy heel into Nature's face."
Hitt provides several examples. "When you camp out, do you swallow your toothpaste? Do you carry out your apple cores and banana peels because they are foreign to the surrounding ecosystem? Do you strain your pasta water and pack out the leavings? Do you smear your faeces across the ground so that the natural processes react immediately and remove your traces within days?"
The new canon of outdoor correct­ness has implications for other pursuits, too. Among anglers, catch and release is out; "touch and go" with a barbless hook is the new standard of sporting propriety. You're not supposed to play the fish; sufficient to know that you've seduced it by your cunningly tied fly. It strikes. It runs. It escapes. As long as your "life forces" have connected, that's all that matters.
In rock climbing, "thou shalt not bolt" is the new credo. Hitt cites the case of a famous name in climbing who, having pioneered and mapped dozens of new routes in the 1970s, has suddenly been smitten by remorse and self-loathing, and is now revisiting those sites and systematically chopping off the bolts he placed 20 years ago. Pity the poor souls who bought his guide books and set out on a climb, only to find themselves halfway up a difficult face looking dumbly at a hole in the rock where a life-supporting bolt was supposed to be.
Mountain bikers have long been branded the devil's henchmen. Whereas tampers flit across the terrain in their superlight air-cushioned, compression moulded, seam-sealed angel boots, bikers churn up the ground in a hellish orgyabrake-smoking, tyre-trashing fury of the damned which stampedes the wildlife and destroys the forest.
Even something as mild as taking underwater pictures is verboten because, supposedly, it traumatises the fish. Body surfing is off limits unless you tread water at all times: by standing up between waves you're crushing the homes of countless burrowing creatures.
Where does this thinking end? "Tread lightly" soon translates into "stay at home." Inch by idealistic inch, we retreat from the outdoor life in order to satisfy an increasingly restrictive code.
Last month, I invited friends to join me on a rafting trip down the Motu River. It was wet and it was wild. Three days of plunging down rapids and ghosting through forested gorges; two nights of camping under a tent fly and cooking over an open fire. One of our number shot a wild pig. To be burning the midnight oil in an Auckland office one night and be eating spit-roasted pork under a star-studded sky the next isn't that part of what this country is about?
In my judgment, we trod lightly: we dug latrines, we packed out our rubbish, our campsites could not be seen from the river. We adopted a code that was appropriate to the time and the place.
"Appropriate" is the key word. Things that are acceptable on the Motu or up the Blue River are out of the question on the Routeburn Track.
During the climb of the Kaipo Wall described in this issue, different environmental practices were applied in different locations. Above the snow line, where the processes of biological decomposition are so slow as to be nonexistent, the climbers took all food scraps and toilet wastes with them. Down in the valley, where, as expedi­tion member Chris North told me, "there's a lot of nature around," they could be less rigorous (and, yes, they tipped out their pasta water).
Enjoyment of nature without damaging the environment; protection without exclusion these are difficult goals. But if we care about the in teg­rity of nature which includes Homo sapiens we should approach the challenges with ecorealism, rather than with the soulless strictures of environmental legalism.

Satellite derived gravity data, originally intended to guide missiles during the Cold War, but publicly released over recent years, is revolutionising knowledge of the Earth's structure in oceanic areas including the vast ocean area around New Zealand.
Commercial fishing operators have been quick to target possible new fishing grounds highlighted on the maps of the gravity data produced by a team of marine geophysicists at the Institute of Geological and Nuclear Sciences (IGNS).
The gravity data is derived from satellite radar altimeters which measure the sea surface height beneath a satellite orbiting the Earth.
Where there is a dense body beneath the sea surface, such as a volcano, the gravitational pull of that body attracts the sea water from adjoining areas, locally elevating the height of the sea surface.
Above comparatively low-density sediment-filled basins or deep ocean trenches, the pull of gravity is less at the sea surface. As a result, water flows to adjacent regions, and the water height is reduced. The difference between high and low areas of sea varies from a few tens of centimetres to as much as a metre or two.
Sea surface height data was partly classified by the United States military until four years ago, when non-military scientists began gaining access to it.
Scientists at research institutions in the U.S. have corrected this sea-surface height data for distorting effects including ocean tides, currents and wave motion. This seemingly impossible task is simplified by the fact that every time the satellite passes overhead, more measurements are made, allowing temporal variables to be averaged out.
The resulting gravity values, combined with known water depths from ship soundings, permit predictions of water depths over unsurveyed areas of the ocean to be made.
Scientists at IGNS have developed techniques for producing maps from all this gravity data, and the result­ing maps show, in never ­before-realised detail, structures that have evolved over the last 100 million years as Earth's surface has been deformed by the movements of tectonic plates.
Not only have the maps been a boon to geophysicists trying to decipher the history of New Zealand's continental area, but they have also revealed previously unknown seamounts and ridges. These previously unfished shallow-water havens are prime targets for fishermen, particularly if they lie outside the jurisdic­tion of the New Zealand fish quota management regime. IGNS has been commis­sioned to produce maps of the data for areas as far away as the middle of the North Atlantic.
The flood of data has been so rapid that scientists are still interpreting the structures revealed. The prominent line of seamounts called the Louisville Ridge, (in the north-east of the map reproduced on the opposite page), has been recognised and interpreted for some years by scientists as a hot-spot trail a sort of burn mark on the Earth's surface created by the motion of the Pacific Plate over a fixed hot-spot in the Earth's interior. (The Hawaiian Islands are the result of the same phenomenon.) The volcanic chain is particularly well defined by the gravity data. However, crossing it at right angles and trending south-west towards the Chatham Islands is a structure that has only become apparent with this release of data perhaps a 100 million-year-old extinct spreading ridge.
A similar spreading ridge where new ocean crust is created as the Earth's plates pull apart is active today in the mid-Pacific. Scientists are still debating the impact such a structure would have had on New Zealand's formation, as well as on plate motion recon­
structions worldwide. A survey involving a U.S. research vessel and scientists in cooperation with N.Z. scientists has been proposed to help resolve the nature and age of the structure.
The long extinct New Zealand-Australia spreading ridge highlighted by darker green at the west of the map is a relic from when New Zealand and Australia stopped moving away from each other 58 million years ago. The gravity map shows previously unrecognised details of the spreading process.
The deep ocean crust to the east of this ridge is bordered by the shallower continental crust of the Challenger Plateau-Lord Howe Rise. This area of the Tasman Sea, which shows in the gravity map many of the signs of stretching prior to splitting apart, is currently being surveyed by IGNS and NIWA scientists as part of the Law of the Sea investiga­tions between Australia and New Zealand.
The deep blue (gravity low) areas to the north-east and south-west of New Zealand mark the Kermadec and Puysegur Trenches associated with the bending down of the Pacific and Indian Plates, which are diving into the Earth's interior in opposite direc­tions at either end of New Zealand.
The gravity lows visible north of East Cape, east of Kaikoura and in the Wanganui Bight are pro­duced by sedimentary basins full of low-density sediment rather than deep water a reminder that this is a gravity map, and that although depth is the main factor in determining gravity, there are anomalies such as these. The basins are principally formed by buckling of the Indian and Pacific Plates as they scrape past each other The deep Vanganui Taranaki basin has proved a good foundry for the generation of most of New Zealand's petroleum resources. IGNS has just published three satellite-derived gravity anomaly maps at a scale of 14,000,000.

Sneaking along with a torch and a spear as the tide drops, waiting for that telltale cloud of sand as the thin, flat shape of a flounder shoots away in front of your feet for many who frequent tidal estuaries, flounder fishing is one of the real joys of life. And freshly caught flounder fried in a hot pan has a wonderfully sweet flavour and deliciously crunchy skin that's hard to beat.
Scientists at the National Institute of Water and Atmospheric Research, Wellington, are trying to capitalise on the popularity of flatfish as they conduct research into finfish species which might be suitable for com­mercial fish farming ventures.
Aquaculture is a relatively new industry in New Zealand. It is undertaken on a small scale, and, apart from salmon, is largely confined to shell fish such as oysters and mussels.
As existing commercial fish stocks become depleted, many countries are looking to aquaculture as a way of harvesting fish in a more sustainable manner.
In New Zealand, the hunt is on for good-sized, fast-growing fish species that could be farmed anywhere in the country and which are good eating.
Initial work by Bob Hickman and Mike Tait suggests that two species of flatfish, brill and turbot, might fit the bill. They are the largest local representa­tives of the flounder family, reaching average lengths of 25 to 45 cm, with exception­al specimens attaining 80 cm in length and weighing 6 kg.
Found throughout New Zealand, both species are most frequently encountered on the inner continental shelf around the west coast of the South Island in depths of 30-100 metres. Like their flounder relatives, brill and turbot are ovoid in shape, and, apart from their greater size, are distinguished from other flounder by their hook-shaped mouths. Primarily brownish gray in colour, both species have the ability to change their colour as camouflage against predators.
Studies on other New Zealand flatfish (such as sand flounder and yellowbelly flounder) indicate that they are fast-growing and short-lived, generally only surviv­ing for three or four years. Brill and turbot, by contrast, may survive to maximum ages of seven or eight.
Juvenile flatfish of many species congregate in sheltered inshore waters such as estuaries and mudflats, where they remain for up to two years. The first spawn­ing occurs at 2-3 years of age. Adult mortality is high, with many flatfish spawning only once, and few spawning more than two or three times. To compensate for this, reproductive capacity is high. Sand flounder release 0.2 million to 1 million eggs each year.
Brill and turbot do not appear to be a common species. Commercial flatfish operations working out of Greymouth often only pick up about a dozen in any one trawl (the rest of the net contents being composed of the more common flatfish species).
Flatfish, as a commercially harvested resource, consti­tute one of our few underexploited fisheries. The annual Total Allowable Catch (TAC) across all species is 6670 tonnes. Since the introduction of the Quota Management System, this limit has never been reached.
Bob Hickman's work to date has concentrated on gathering information on the reproductive cycle of both species. This has involved catching fish during the spawning season (winter and spring) and artificially inseminating the eggs. So far this has proved to be an extremely difficult process, but some offspring have resulted, and lived for at least four months.
The next phase of the research will involve finding out what controls the success of fertilisa­tion and what is involved in rearing quantities of larvae to the juvenile stage. Researchers will also be looking into the natural diet of fish to determine what should be included in feed pellets.
Since flatfish are bottom feeders, they should be well suited to land-based farming in ponds and races more so than salmon, for example, which are usually grown in sea cages.

My kids yearn to visit the United States. It is the home of such cultural icons as Baywatch and Coca-Cola, rock groups too numerous to mention, fine cuisine such as KFC, and just about every­thing that's cool.
Cruel parent that I am, I tell them that their best shot at getting there is to win the annual National Science and Technology Fair for school pupils. And I'm serious. It wouldn't be easy, because there are a lot of excellent entries, but it's far from impossible.
First, though, you must choose the right sort of project. Don't cut out a few New Zealand Geographic pictures of Mt Ruapehu erupting, combine them with a papier mâché model of a volcano and add a bit of text from Microsoft Encarta if you wish to succeed. Instead, embark on your own investigation or technologi­cal development, and allocate plenty of time to do it. A few days or even weeks of intermittent effort won't be enough. Three months is a minimum, and a year is preferable. To the judges, every line of your own carefully investigated results is worth pages lifted from a book.
Learn some lessons from the national finalists in last year's contest, held in December in Christchurch.
Main prizewinner Andrew Drake's project was based on observations he had first made in 1994 of mangroves growing, not in their habitual mud, but on the intertidal lava fields of Rangitoto Island. Subse­quently, he has found mangroves colonising other Auckland intertidal lava fields. But they do not seem to be just any mangroves. The rock-loving variety is a hitherto unrecorded pros­trate form that lacks a trunk. Since silt readily builds up around its many stems, Drake predicts that this plant could result in the burial of all Auckland's estuarine volcanic foreshores in the not-too-distant future.
Arama Ehau and Hamiora Werahiko (Rotorua Boys High), studied burial of a different type: that of food in a hangi. Back in 1994, they began assessing different rock types for their ability to store heat and release it gradually, using simulated hangi boxes and temperature probes. Andesite and mica schist proved the most effective rock types. Over the last two years, they have concentrated on what types of wood best heat the stones. While tawa, rata, manuka, kanuka and pine all scored well in test situations, rata, manuka, and kanuka per­formed best in the heat of the hangi. However, to the students' astonishment, when the amounts of wood used were converted from volume (the way firewood is sold) to weight, an almost identical amount of heat was produced by the same weight of wood, regardless of species.
Truth often leads in unexpected directions. Sometimes in lower echelon Science Fair projects it's hard to even see which way it has gone, but not in the national finals. However, that's not to say that every­thing here always goes as planned. Nicholas Lloyd of Tauranga tried to figure out whether the terpenes present in waste citrus fruit could be extracted and put to use.
While he succeeded in extracting the oils and finding uses for them, you had to have a lot of tangelo peel to retrieve not much citrus oil. When he tried to chemically synthesise some of the constituents, success eluded him. But there is no doubting that he learnt a lot.
Reuben Miller's wood gasification machine tried to use heat from an engine exhaust to generate combus­tible gases such as carbon monoxide from waste wood chips. Although the levels of flammable gases increased in his heated samples, the gases given off could not be ignited so it's back to the drawing board.
Less open-ended investi­gations which lack the risks and possible rewards of these more ambitious projects are probably the most popular type of entry. Comparing weight gains of drenched and undrenched lambs over winter (the more expensive drench was worth the extra money), comparing house paints, analysing calligraphy inks, finding substances that will protect vegetables from assault by chooks (but am I going to enjoy lettuce that has been sprayed with lavender, fish fertiliser or seaweed manure?), develop­ing nesting boxes for the Department of Conservation to use in bird transfers, studying respiration in backswimmers, examining drinking water for harmful bacteria and evaluating possible antidotes for nettle stings were all grist for projects that made it to this year's finals.
Many legitimate projects straddle the fuzzy boundary between science and technol­ogy, and awards are made for technological projects. Overall winner here was Sarah Snell from VVhangarei, with a bathroom fan pow­ered by shower water. Unfortunately, her house lacks mains pressure hot water, so in the interests of making the fan work effectively, cool showers were necessary. A pair of Marlborough girls developed an improved design of school backpack that put less stress on backs, and was very highly rated by most pupils who tried it. Ruyan Mendis and Anthony Lander constructed a cricket bowling machine with which they ascertained that swing in the flight of the ball depends on the seam, and how it is angled by the bowler. The seam produces turbulence, which causes the ball to deviate from a straight line. A slower bowling speed and an old, rough ball maximise the deviation.
Otago intermediate school pupils Anna Clague and Amanda Wast developed a high calcium drink that teenage girls would enjoy as well as knowing that it contributed to bone bulk, heading off osteoporosis later in life. "Apricool" was a mixture of yoghurt, fruit juice and fruit purée that proved very popular with their friends and taste panel.
One of the fascinations of the National Science and Technology Fair is looking at the ages of the exhibitors and their geographic spread. All seventh formers from Auckland Grammar and Christ's College? Not a bit of it. Morrinsville College was the only school to have three national finalists. Others came from Whangaparaoa Primary, Waimea College, Napier Intermediate, Rangi Ruru Girls School, Tyndale Park Christian School, Manurewa High School, Levin Interme­diate and Okaihau College, to name a few, and the main prize winners hailed from Whangarei Girls High (Sarah Snell) and Carey College, a small Christian school in Auckland (Andrew Drake).
In the last couple of years there have been markedly more entries from younger pupils, and fewer from seniors. In local fairs with perhaps a total of 20,000 entries nationwide three­ quarters of entries now come from fourth form or more junior students.
Start thinking now. Projects usually need to be ready by August, and you won't make it to America without a major effort.

Symbol of the warmth and charm of fa'a Samoa—the Samoan way—the gaily decorated communal pool is a focus of village life. As children frolic, its waters rinse away the grime of the day. Later, adults will seek out its coolness, washing together and talking as the sun sets. Yet beneath an apparently relaxed surface run troubling undercurrents, as Western ideas of individual freedoms challenge a rigid, traditional society where family and village are everything.

Ten years ago, astrono­mers were monitoring the departure of Comet Halley from the inner solar system while the public grumbled that they had been had.
In fact, the public had had unrealistically high expecta­tions of the 1986 return of this most famous of comets.
Several of its previous appearances had been sufficiently bright to attract attention without the benefit of publicity, and been recorded in weaving or paint. In 1910, the comet's last appearance, it was singularly favourably placed and relatively close to the earth, so that its brilliant tail extended right across the night sky.
In 1986, interest was swelled by publicity from the astronomical community, for this was to be the first time that space probes would investigate the coma (the veil of gas and dust which is the visible part of a comet) and nucleus, revealing that which is forever invisible from Earth. To many an entrepre­neur all this added up to the marketing opportunity of a lifetime, and it was exploited to the full with all the hype and misinformation that typifies such exercises.
So it was that Instamatic cameras were loaded with colour film in the expectation of frame-filling super­saturated colour images and great was the disappoint­ment when they did not materialise.
Comet Halley actually performed very much as the astronomers had predicted, and their efforts to probe the coma were amply rewarded by photographs of the nucleus, as well as other data sent back by the probe Giotto. The dirty snowball turned out to be a 12­kilometre-long peanut with
an unexpected jet-black skin pockmarked with vents from which evaporating material poured into space. Addi­tional results came from two Vega probes and two Japanese probes monitoring the coma. But the hucksters had done their job only too well, and to this day one hears that Halley "was a flop," that the scientists "had it wrong."
Although there are hundreds of known comets, and a dozen are discovered or rediscovered each year, Hale-Bopp immediately attracted a good deal of attention. When it was discovered on July 23, 1995 simultaneously by Alan Hale in New Mexico and Thomas Bopp in Arizona, C/1995 01 proved to be rather more than seven astronomical units (AUthe distance of the Earth from the Sun) away from us. This placed it about halfway between the orbits of Jupiter and Saturn.
Comets are normally invisible out there, for it is so cold that such coma as there may be is of hydrogen, which is quite invisible, and the tiny nucleus is a minute black spot on a black background. Not until they have ap­proached to within about 3 AU of the Sun does the Sun heat the surface enough for water ice to start sublimating and so develop a visible coma. For Comet Hale­Bopp to be visible at such a distance suggested that it might be spectacular when it approached Earth.
Some suggested that it could be the brightest comet since the great comet of 1577; unlikely to be visible in daylight, but bright enough to be immediately seen at dusk as a rival in brilliance to Sirius and Canopus.
But don't bet your shirt on it. Many comets have shown great promise before perihelion their closest approach to the Sun only to reappear from that encounter as cinders rather than Cinderellas, with their available ice virtually all evaporated, and the splen­dour of their pre-perihelion tail but a pathetic remnant.
One reason suggested for Hale-Bopp's visibility is that the solid icy nucleus may be unusually large, 10-40 kilometres. Other reasons could be that it is particularly dusty and contains a lot of frozen carbon monoxide, which sublimates at a lower temperature than ice does.
Analysis of its very elongated orbit reveals that Hale-Bopp is a long-period comet that was last here 4200 years ago, at about the end of the Old Kingdom when the Great Pyramid was young and pharaoh Pepi II ineffectually struggled to maintain his authority against his increasingly independent barons.
The comet's orbit is almost perpendicular to that of Earth and the other planets in our solar system. However, this time the positions of the giant planets Jupiter and Saturn will change the comet's orbit, shortening its period to 2400 years
Constantly under obser­vation since its detection, Hale-Bopp has not behaved as expected. Normally, comets appear to brighten in a fairly regular manner as they approach the Earth and the Sun. Hale-Bopp's increase in brightness as it swept towards perihelion was irregular, making the always dicey game of predicting maximum brightness even more fraught with difficulty than usual.
Atypical phenomena bring the wild-eyed out of the woodwork to meet the bug-eyed, and Hale-Bopp hs been no exception. Chuck Shramek of Houston, an amateur astronomer, captured an image of the comet on the night of November 14 which ap­peared to show a "Saturn-like object" close by. Since the star-charting computer programme that he was using for reference did not show any star in this position, Shramek assumed that he had discovered a new planet. Rather than seek independ­ent confirmation, Shramek trumpeted his news on the nationally syndicated Art Bell Show, known for its credulity over reports of UFO abductions, spacecraft landing in the back paddock or any of the more dramatic types of paranormal event.
A quick check by a number of astronomers, including Alan Hale, immediately revealed that there was a star just where the "new planet" was reported, and that the "ring" was no more than a diffrac­tion spike generated by the optical system. Far from abashed, Shramek main­tained the non-stellar reality of the Saturn-Like Object (SLO), and was joined by a number of other observers, who claimed that they had recorded "changes in course," and see the SLO as an alien space craft using Hale-Bopp as cover. Thirty-nine members of the Heaven's Gate movement used this information as their "ticket to ride" when they committed mass suicide this Easter.
Comet Hale-Bopp's closest approach to Earth was on March 22, but it was then still 197 million kilometres distant. Perihe­lion was on April 1, when it was 136 million kilometres from the Sun. At that time the comet was travelling at 44 kilometres per second.
For New Zealanders, viewing Hale-Bopp will not be easy, for its closeness to the Sun means that when the comet is nearest and bright­est, it will be in the early evening sky. As this article goes to press, with the comet drawing away from the Sun, it will be visible for longer after sunset, and then after dusk, but by the same token it will be becoming fainter as its surface cools.
The diagram, adapted from that in The New Zealand Astronomical Yearbook, 1997, Grant Christie & Stan Walker, shows the position of the comet at various dates just after sunset. Along the Ecliptic, the Sun is shown at the appropriate dates together with the line of the horizon at Auckland (diago­nal lines), and the comet is shown sized according to its estimated brightness, and also dated.
Because the figure shows half the celestial equator and its constellations (i.e. 180° or 12 hours), and the Earth's axis of rotation is at right angles to the celestial equator, distances on the diagram measured parallel to the celestial equator can be read off as times. 200 mm = 12 x 60' so 1 mm = 3.6 minutes.
Do not count on seeing the comet immediately after sunset, for in April civil twilight is 30 minutes after sunset, and nautical twi­light getting seriously darknot for another 30 minutes. To further con­found us, the moon is full on April 23, May 22, June 21 and July 20, which means as we wait for the sky to darken the rising moon frustrates us. Note that before the full moon, the moon rises earlier than sunset; after full moon it rises progressively later than sunset, so it is these latter evenings which are our window of opportunity.

Holiday makers generally put up with a lot of over­ crowding at seaside camping grounds, but last summer, when offered the chance to share their tent sites with a couple of decaying tropical cyclones, thousands thought discretion the better part of valour.
Cyclone Fergus, the first notable meteoro­logical tourist of the summer, brought torrential rain and damaging winds to parts of the North Island between Christmas and New Year. There was no loss of life, in part because of timely warnings about the ferocity of the storm.
Following close on the heels of Fergus, Cyclone Drena caused more wind damage but brought less rain. The combination of wind and extremely high tides caused millions of dollars' damage at Thames, and a man was electrocuted when he grasped a fallen power line in order to pull himself up a bank.
During the summer the Pacific was influ­enced by a weak La Nina event which caused the flow over the North Island to be from the north-east more often than normal. This helped steer Fergus and Drena over the North Island, as well as causing persistent humid weather in Auckland.
Tropical cyclones form over the warmer waters of the South Pacific Ocean from November to early April in the presence of high-level anticyclonic outflow and low-level vorticity associated with outbreaks of thunderstorms in the South Pacific Convergence Zone
As they move away from the tropics and over colder waters, tropical cyclones weaken and lose much of their characteristic structure. In particular, the narrow ring of cumulonimbus clouds known as the "eye-wall," which produces heavy rain and is surrounded by the relatively small area of maximum winds, breaks up and weakens.
For two tropical cyclones to form in the tropics close together in space or time is not unusual. However, for two to take such similar paths as Fergus and Drena when they leave the tropics is rare, although not without precedent.
In the ten cyclone seasons The Weekly News told the tale of destruction in 1936.
Before this one, the low centres of four decaying tropical cyclones passed over New Zealand, while another five, such as Bola in 1988 came close enough to affect New Zealand's weather. In addition, another three contributed to record floods in parts of New Zealand because of the warm moist tropical air their wind systems brought over the country, even though their centres of lowest pressure stayed well away from the land.
In a small number of cases, the remnants of a degenerating tropical cyclone combine with a trough of low pressure in the mid-latitude westerlies to produce a deep depression surrounded by a very large area of damaging winds and heavy rain. Such an event is most likely to occur in the second half of summer, or in autumn, when the sea surface temperatures are highest, allowing the tropical cyclones to maintain intensity for longer as they move south.
This happened with Cyclone Bola, which flooded Gisborne and Northland in March 1988, and with Cyclone Gisele, which sank the Wahine in April 1968. It also happened with an unnamed tropical cyclone that crossed the North Island on February 2, 1936.
Although this last event seems to have largely passed from popular memory, it may well have been the most destructive storm to have hit the North Island this century. It formed south of the Solo­mon Islands at the end of January and re-developed as an intense mid-latitude depression when it met up with a cold front over the North Tasman Sea.
As the cyclone crossed the country, the North Island sustained heavy rain in most areas, bringing most of the major rivers into flood. The Mangakahia River in
Northland rose 19 metres at Titoki. Kaitaia's main street flooded a metre deep, and one man was drowned when a house was washed away.
In Whangarei, almost 300 mm of rain fell in 24 hours, and floodwaters raced through the business district, tearing up footpaths and entering buildings. Gelignite was used in an unsuccessful attempt to clear driftwood piled against Victoria Bridge, which carried the road to Whanga­rei Heads, where several cottages were blown down.
At Waitangi, the water rose two-and-a-half metres in 20 minutes, forcing eight men sleeping on the floor of the Tung Oil Company's cookhouse to take refuge on the roof. When the struc­ture began to move they clambered into a tree overhanging the cookhouse, which was later carried away by the flood. A train was marooned by washouts near Kaikohe, and 60 passengers had to spend the night in the carriages.
Torrential rain fell on the until increased pressure carried away the obstacle and an enormous body of water swept down the river bed, carrying away a large bridge and damaging four kilome­tres of road. Both banks of the river were swept clean of soil and vegetation.
One observer saw rimu and kahikatea trees borne along by the torrent rear up when their roots or branches caught against some obstacle, and topple end over end with a crash that could be heard for miles. When the water subsided he picked up 40 dead trout and counted hundreds of eels killed by the rushing timber and large boulders carried along by the flood.
In Hawkes Bay, the Tukituki River flooded the settlement of Clive, cutting the road and rail link between Napier and Hast­ings and drowning 1500 sheep in stock yards. The Tukituki also broke its bank at Waipukurau, drowning thousands of cattle and sheep and forcing the evacuation of 70 houses.
Roads and railways were inundated by floods and undermined by washouts, bridges were destroyed, and slips came down in their thousands all over the North Island. Near Stratford the main trunk line was blocked by more than a dozen slips, the biggest of which was 500 metres long and full of trees.
In the Wairarapa, the Ruamahanga flooded farmland, cutting off Martinborough, and the Waipoua flooded several streets in Masterton. At Kopuaranga, just north of Masterton, a 14-ton traction engine disappeared into a river normally only a metre deep, and still had not been found several days later. At
Castle Point, the sea washed away the sandhills and invaded houses 100 metres inland.
Wind associated with the cyclone lashed the country from Picton to Kaitaia. Palmerston North was among the hardest hit towns. Houses lost roofs, chimneys were blown over, the grandstands of the A & P Association, the Awapuni Racecourse and the sportsground were demol­ished, and a man was killed when he was blown off his roof as he tried to repair it. A train was derailed near Makerua when the last two carriages and the guard's van were caught by the wind and thrown down a bank.
At Longbum, the Anglican church was demolished and scattered over the road and railway line. A horse on a nearby farm was cut in half by a flying sheet of corrugated iron. Three huts next to the railway station were blown over. One somersaulted three times with the occu­pant rolling about inside with a heavy stove. His wife had just stepped outside when the but lifted and toppled over, missing her by a foot. She was blown into a clump of willow trees and had to be extricated by the stationmaster.
The Feilding Aero Club hangar was blown away and the two planes inside destroyed. In true Twister style, a motorist on the main road near Te Matai was chased by a large corrugated iron tank that raced across the paddock towards him. It jumped the fence, but luckily only struck his car a glancing blow.
Buildings were also blown down in Taranaki and in the Bay of Plenty, and the wind wrought havoc in orchards all over the North Island destroying a large portion of the crop. In Wairoa apples and pears were seen flying horizontally for some distance from the trees. Crops like maize, wheat, and oats were flattened from
Marlborough to Northland, haystacks blew away in many places, and, in Pukekohe, potato plants were sheared off at ground level.
In Auckland, 40 boats were sunk or driven ashore in the Waitemata Harbour and several more in the Manukau Harbour. In Wellington, disaster was only narrowly averted when the interisland ferry Rangatira steamed into rocks near the mouth of Wellington Harbour. After 20 minutes stuck fast she was able to reverse off the rocks, then turn and back slowly up the harbour. Taking water in through gaping holes in her bow, her propellers were half out of the water by the time she grounded next to the Clyde Quay wharf, and her forward lower passenger decks were awash.
At the height of the storm, trees were uprooted from ridges in the Tararua Ranges and thrown into the valleys. Trampers described whirlwinds twisting the crowns of trees around until all the branches splintered off.
Just as Drena followed Fergus last summer, so the great storm of February 1936 was followed by another decaying tropical cyclone in March, which affected a smaller area of the North Island, but caused more damage in some places.
Although accounts of the effects of cyclones last summer concentrated on death and injury to people, and damage to property, there was one story about the impact on wildlife. Orni­thologists visiting the gannet colony at Farewell Spit as Cyclone Drena passed by witnessed the combination of high sea levels and big waves inundate almost 90 per cent of the nests, drowning the chicks as the adults flew off.
One doughty chick was washed off its nest four times, but climbed back on, and was still there when the ornithologists left.

Boiling water and the stench of sulphur hardly seem a combination conducive to life, yet some bacteria thrive in such hostile environments. Biologists are beginning to think that the first life forms on Earth may have been similar to these hardiest of living things.

Like an Amazonian hunter , blowpipe at the ready, the zoologist stalks his quarry. Halfcrouching, his every movement slow, deliberate, noiseless, he lifts the metre-long pipe to his mouth, takes aim, and, with cheeks bulging, delivers a blast of air down the pipe.